a last-minute venue change, from a giant outdoor stadium, seating 73,000 people, to the smaller arena. supposed to seat about 15- to 20,000. the democratic national convention saying it was due to weather. it was a kind of monsoon this afternoon. and today the president spoke to those who will not now be here. he spoke via conference call. >> my main message is, we can't let a little thunder and lightning get us down. we're going to have to roll with it. >> another casualty of the last-minute move, those balloons, we always see waiting up in the rafters, hundreds of thousands of them, no time to blow them up or get them ready. if we look right down there, right now, in the center of this arena, we can see some confetti cannons. small bags of confetti, there they are. take our word for it, they're in position and they're going to be the substitute. time now to bring in george stephanopoulos. >> the confetti will have to do.